FWIW, I recently jumped ship and installed Ubuntu over MacOs on my Macbook Pro (not dual booting), and it was as easy as can be reasonably expected. The worst side effect so far is that a strange red light is emitted from the headphone jack. It's been more-or-less flawless. Oh yeah, I also had to google for about ten minutes to find an askubuntu question about running web videos that depended on silverlight. I must admit I don't entirely understand what I installed (from apt), but it worked and in total maybe a half hour was lost.

I would have a much worse experience transitioning to windows, or even in all likelihood transitioning back to MacOs.

Of course, having linux interoperate with MacOs is a completely different situation. That said, for a while I dual-booted with grub, and it worked fine. In booting from usb, dual-booting, and running only linux on mac hardware, I never experienced track pad or keyboard failure, though I do think apple's keyboard layout is inferior for non-MacOs systems. I expected to have some major problems using Ubuntu exclusively, but I have had few hard-to-fix problems. It was hardly a nightmare.